1. Field
Apparatuses and methods consistent with the exemplary embodiments relate to a method and apparatus for optimizing a camera for color calibration of multi-displays, and more particularly to a method and apparatus for optimizing a camera, in which optimized settings for a white balance and exposure suitable for color calibration of multi-displays are automatically determined so a user can easily perform the color calibration.
2. Description of the Related Art
With an increase in demand for display-based advertisement, multi-displays have been configured as a video wall, in which multiple displays are connected together to form a single, large screen. In this case, a fabrication error, variation in display characteristics as on the display ages, etc. cause difference in color among the displays. To solve this problem, color calibration among the displays is necessary.
A conventional calibration method employs a spectrophotometer that can measure the tristimulus values (XYZ) of light. In this conventional method, the spectrophotometer has to contact the display, and it is thus difficult to approach the display if the display is installed at a location that is not easily accessible. Also, in the conventional method, the color calibration is performed for every individual display, and therefore calibration time increases.
Meanwhile, calibration may be performed using a camera instead of using the spectrophotometer. If the camera is used, calibration is convenient because multiple displays are photographed at a single time.
FIG. 1 is a block diagram showing a conventional color calibration apparatus 30 using a digital still camera (DSC) 32 for calibrating multi-displays 10 which displays the image from the image displaying device 20.
The conventional color calibration apparatus 30 includes a color calibration image display 31, which displays an image for calibrating on the plurality of displays; an image acquisition processor 33, which photographs a color calibration image and acquires a photographed image; an image adjustment processor 34, which performs an image adjustment process with regard to the photographed image; a target chromaticity calculation processor 35, which calculates target chromaticity from the photographed image after the image adjustment process; a color calibration coefficient calculation processor 36, which calculates a color calibration coefficient; and a color calibration processor 37, which applies the calculated color calibration coefficient to the display.
Such a conventional color calibration apparatus 30 of the multi-displays 10 employs a raw image to adjust a white balance in the image adjustment processor 34 and adjust exposure settings in accordance with the purpose of the multi-display. If there is no guide to camera settings and a user is not very knowledgeable about the color calibration, it is difficult for the user to determine the proper camera settings. Although the raw image is advantageous to exclude effects of data processing (e.g., white balance adjustment, etc.) in a digital camera, a decoding process of an input data is needed because encoding formats are different among manufacturers. Further, the data size of raw image is large.